blue halo on backlit subjects

hi,

i don't know if this has already been discussed but i'm getting a bluish halo around the edges of backlit subjects, especially around the hair. Also this blue creeps into strong relections off shiny hair.

is there anything i can do about this (either in camera or in post production) or is it just a digital phenomenon i've got to get used too?


Kit- Hasselblad H2 with P30 back, 80mm and 150mm lens.
tethered to MacPro Quad Duo.

all help much appreciated.